The upgrade to IE7 from IE6 is free - its more like if MS made Vista free for everyone with an XP lisence, then hell yeah I'd upgrade to Vista
IE6 isn't very good at rendering a lot of things, that's my gripe with it - and really it's not a lot of effort for someone to upgrade their browser to IE7... It's not that old (year 2000ish isn't it?) but it's quality is pretty damn poor, and there's a free upgrade available which will be better for the end user and the web developers. Win-win, surely!
If YouTube had a notice when IE6 users visited explaining simply and quickly to the user that they're using an old browser, and explained simply how to upgrade to a new one, then that'd only be a good thing.
I honestly do think that IE6 users should upgrade - they'll loose nothing but gain a lot.
I know exactly what you mean though, iCraig, you shouldn't have a site decide who it displays its content to, and a site should work with all the popular browsers... but it seems too many people just aren't aware of how much of a pain IE6 can be to web developers - and the only reason they're unaware is because web developers still cater for them. It would make things so much easier if nobody used it, and nobody would loose out on anything - they'd only gain a better browser. I bet that if IE6 users were actually aware their browser is outdated, less secure, poorer at rendering, and making developers lifes difficult, they'd upgrade it... it's the unawareness (word?) thats the problem, I guess.
I'm sure you see from my point of view, and I do see from yours

But you must agree it'd be for "the greater good" if everyone was on IE7. I just think that maybe something needs to be done to make people aware of it, if IE6 doesn't become a dying breed within the next 18 months or so?
sorry for the read, didnt realise how much i typed!